Control of vapor electric devices



Jan. 15, 1929. 1,699,113

Y. MATUNAGA CONTROL OF VAPOR ELECTRIC DEVICES Filed Oct. 9, 1926 Inventor: Yosinobu Mauuna a;

by "T His Attorney- Patented-Jan. 15, 1929.

UNITED STATES PATENT OFFICE.

YOSINOBU MA'IUNAGL, OI TOKYO, JAPAN, ASSIGNOB TO GENERAL ELECTRIC COM- rm, A CORPORATION OF NEW YORK.

common or varon nmao'rnrc nnvrcns.

Application filed October 9, 1928, Serial No. 140,6 49, and in Japan December 30, 1925.

My invention relates to the control of vapor electric devices, and has for its principal object the provision of an improved apparatus whereby the arc of such a device may be maintained irrespective of variation in the load and temperature conditions under which it is o erated.- A further object is the provision 0 means for ensuring quick starting and smooth operation of a vapor electric device, such as a mercury rectifier or the like.

It is known that the current required to maintain an arc in the mercury rectifier is dependent on the temperature at which the rectifier is operated. Thus, upon adecrease in the operating temperature of the rectifier, the pressure of the mercury vapor decreases, the voltage between the cathode and anode increases, and the arc is eventually extinguished unless means are provided for preventing too great a decrease in current. In accordance with my invention, this difiiculty is avoided by the provision of means operable to vary the exciting current of the rectifier in a manner to ensure continuity of the arc underthe various load and temperature conditions'to which the rectifier is subjected. My invention will be better understood from the following description-when considered in connection with the accompanying drawing, and its scope will be pointed out in the appended claims.

-The drawing shows a rectif ing apparatus to which my invention has een applied.

This apparatus comprises a mercury rectifier 1 provided with main anodes 2, exciting anodes 3, a cathode 4 and a starting anode 5. Current is supplied to the exciting anodes 3 from a suitable source through a transformer 6 comprising a secondary Winding which has its end terminals connected to the exciting anodes3 and is connected at a point intermediate its ends to the cathode 4 through impedance devices shown as resistors 14, 15 and 16.

A thermal responsive device 7 operable in response to the current produced by a thermo-electric pile 8 mounted within or adjacent to the rectifier 1 is arranged to control the connections of the resistors 15 and 16 in accordance with the temperature of the rectifier. The device 7 is provided with a movable member 9 which may be utilized to indicate the temperature of the rectifier and with contacts 10 and 11 which are arranged to engage a contact mounted on the end of the member 9 for the purposeof completing c rcuits whereby the operating coils 12 and 12' are respectively connected to sources of current shown as batteries 13 and 13'. v

The operation ofthe apparatus will be readily understood if it be assumed that the transformer 6 is energized but the temperature of the rectifier 1 is toolow to permit starting of its exciting current at the existing temperature. Under these conditions, the contact on the end of the member 9 is moved either into engagement with the contact 10, or with the contact 11. When the contact of the member 9 engages the con tact 10, the operating coil 12 is energized,

and the resistor 16 is short-circuited by the switch 17, thus increasing the potentials applled to the starting and exciting anodes. If this increase in potential is insufiicient to start the arc of the rectifier at the existmg temperature, contact, is made between the end of the member 9 and the contact '11, thus producing closure of the switch 18 whereb the resistors 15 and 16 are both short-circuited and the starting and exciting anode potentials are increased to a point at which startin of the arc is ensured.

Likewise, i the temperature of the rectifier decreases during its operation, interruption of the arc is prevented by the increase.

in exciting anode potential produced by operation of the switches 17 and 18. My invention thus provides a simple and reliable means whereby starting and operation of the rectifier is rendered to a large degreeindependent of the ambient temperature.

The embodiment of the invention illustrated and described herein has been selected for the-purpose of clearly setting forth the arranged to apply a potential to said electrodes, and means operable to Control said potential in accordance with the tempera ture of said device.

2. The combination of a vaporelectricdevice comprising excitingelectrodes, means arranged to apply a potential to said electrodes, a thermal responsive element arranged to operate in accordance with the temperature of said device, and means for varying the magnitude of said potential in response to the operation of said element.

3. The combination of a vapor electric-device comprising exciting. electrodes, means arranged to apply a potential to said electrodes, a thermal responsive element mounted within the casing of said device, and means arranged to vary said potential in accordance with the operation of said element.

'4. The combination of a transformer comprising a winding provided with a plurality of terminals, a vapor electric device provided with arrelectrode connected to one of said terminals and with a cathode, an impedance element connected between said cathode and another of said-terminals, and means arranged to control the connections of said impedanceclement in accordance with the temperature of said vapor electric device.

5. The combination of a transformer comprising a winding provided with end and intermediate terminals, a vapor electric device provided with an exciting anode con nected to an end terminal and with a cathode, a plurality of impedance elements connected between said cathode and said in termediate terminal, and means arranged to progressively control the connection of said impedance elements in response to variation in the temperature of said vapor electric device.

In witness whereof, I have hereunto set my hand this 20th day of September, 1926.

YOSINOBU MATUNAGA. 

